﻿using System;
using System.ComponentModel;
using System.Windows.Data;
using System.Windows.Markup;

namespace Orz.Framework.Foundation.Converters
{
    /// <summary>
    /// Provide a Converter swap the Convert and ConvertBack.
    /// </summary>
    [DefaultProperty("Converter")]
    [ContentProperty("Converter")]
    public class ReverseConverter : IValueConverter
    {
        /// <summary>
        /// Gets or sets the converter.
        /// </summary>
        /// <value>The converter.</value>
        public IValueConverter Converter { get; set; }

        #region IValueConverter Members

        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value produced by the binding source.</param>
        /// <param name="targetType">The type of the binding target property.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (Converter != null)
                return Converter.ConvertBack(value, targetType, parameter, culture);
            return null;
        }

        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value that is produced by the binding target.</param>
        /// <param name="targetType">The type to convert to.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (Converter != null)
                return Converter.Convert(value, targetType, parameter, culture);
            return null;
        }

        #endregion
    }
}
